Conventionally, motorized cutters having engines ("engine cutters"), electric motor cutters, and the like are used for cutting various materials. In the conventional engined cutter, a cutter blade is attached to a drive shaft that is adapted to be rotated by a motor, such as a small air-cooled two cycle gasoline engine. FIG. 1 presents a typical rotating disc-shaped cutter blade 2 held by an arm 1a extending from an apparatus body 1.
The cutter blade 2 may be replaced with a resinoid blade, powder blade, diamond blade, etc., depending on the materials to be cut. However, in some cases the cutter blade may have a fitting hole with a diameter that differs from that of the cutter, such that the cutter blade 2 cannot be attached to the drive shaft of the cutter. To allow use of the cutter with these types of blades, in the prior art, several collars may be used, each having a different diameter, which are designed to be placed between the drive shaft of the engine cutter 1 and the cutter blade 2 when installed. Typically, the diameters of the fitting holes of such conventional cutter blades are 25.4 mm, 27 mm and 30.5 mm.
As described above, when several collars, each having a different diameter, are used, because the collars often constitute comparatively small parts, they may be easily lost, and, as a result, much care must be taken to manage these collars while not in use. In addition, the replacement of the cutter blades having collars requires much more labor than replacement of blades not requiring collars.